This is the first Gordon Research Conference on the biology of the spirochetes. Because of the rapid pace of the molecular and genetic analysis of spirochetes brought about by modern technological advances, an ongoing conference to bring investigators together to exchange information is of major importance. The need for this conference became quite obvious after an international meeting entitled "Molecular Biology of Spirochetes" in Annecy, France which was held in October, 1991. Spirochetes are a phylogenetically ancient group of bacteria. These organisms have a unique overall structure and mode of motility. In addition, they cause and are associated with several important diseases including syphilis, lyme disease, leptospirosis, periodontal disease, relapsing fever, and swine dysentery. Because there are no established genetic exchange systems in spirochetes, and because spirochetes are comparatively difficult to cultivate, progress in understanding the biology of these bacteria let alone how they cause disease is considerably less advanced than with other bacterial species. Pulsed field gel electrophoresis, DNA amplification by the polymerase chain reaction (PCR), and other modern techniques have given us new and exciting information and insight into the genetics and biology of these organisms. The Gordon Research Conference will be the ideal setting for information exchange and developing collaborations. The conference, which is anticipated to have 110-135 attendees, will permit scientists from the United States and abroad to discuss recent developments and ideas regarding the biology of spirochetes. Funds from this grant will help support the expenses of session chairs, speakers, and graduate students and postdoctoral fellows. Sessions will emphasize the emerging molecular and genetic approaches in the analysis of Treponema, Borrelia, Leptospira, and Spirochaeta. Comparisons will be made among these different genera of spirochetes, and how they differ from other species of bacteria. Molecular mechanisms concerning the interaction of the spirochetes with host cells and tissues will be a key element in the conference.